In lathe machining, a cylindrical work piece is rotated along a horizontal axis for cutting of the work piece typically using a single-point cutting tool. To provide cutting of the outer diameter or inner diameter of the work piece according to precise requirements, it is important to center the cutting tool along the horizontal plane extending through the turning axis of the work piece prior to initiating a desired cutting operation. While many tools have been used to assist an operator in centering the cutting tool for cutting the outer diameter of a work piece, these tools are often unnecessarily large and bulky as compared to the size of typical work pieces having a diameter as small as about 3 inches, which makes them inapt for centering the cutting tool when making inner diameter cuts (such as enlarging a hole already drilled into the work piece).